Baked Seafood Au Gratin

[elie]

1 onion, chopped
1 green bell pepper, chopped
1 cup butter
1 cup all-purpose flour
1 pound fresh crab meat
4 cups water
1 pound medium shrimp, peeled and deveined
1/2 pound bay scallops
1/2 pound flounder fillets
3 cups milk
1 cup shredded sharp Cheddar cheese
1 tablespoon distilled white vinegar
1 teaspoon Worcestershire sauce
1/2 teaspoon salt
1 pinch ground black pepper
dash hot red pepper sauce
1/2 cup grated Parmesan cheese

Lightly grease one 13×9x2 inch baking dish. In a heavy skillet, saute the onion and the pepper in 1/2 cup of the butter or margarine.
Cook until tender. Stir in 1/2 cup of the flour and cook over medium heat for 10 minutes, stirring frequently. Add the crabmeat and stir well. Press this mixture into the bottom of the prepared baking dish and set aside.
In a large Dutch oven, bring the water to a boil. Add the shrimp, scallops and flounder. Simmer for 3 minutes. Drain and reserve 1 cup of the cooking liquid and set the seafood aside.
Preheat oven to 350F. In a heavy saucepan, melt the remaining1/2 cup butter over low heat. Stir in the remaining 1/2 cup flour.
Cook and stir constantly for 1 minute. Gradually add the milk plus the 1 cup reserved cooking liquid. Raise heat to medium and cook, stirring constantly, until the mixture is thickened and bubbly. Stir in the shredded Cheddar cheese, vinegar, Worcestershire sauce, salt pepper, and hot sauce. Add the cooked seafood and stir gently.
Spoon the seafood mixture over the crabmeat crust and sprinkle with the Parmesan cheese. Bake in the preheated oven for 30 minutes oruntil lightly browned. Serve immediately.